Benign Hypertrophied Column of Bertin Mimicking a Renal Tumor in a Child: A Diagnostic Challenge.

The hypertrophied column of Bertin (HCB) is a benign anatomical variant of the renal cortex that may mimic a neoplastic mass, particularly on ultrasound, potentially leading to unnecessary diagnostic or surgical interventions. We report the case of a nine-year-old girl in whom a renal lesion was incidentally discovered during follow-up imaging for a post-traumatic subcapsular hematoma. Renal ultrasound revealed an isoechoic mass in the mid-portion of the left kidney, extending into the renal sinus. Color Doppler demonstrated a vascular pattern similar to the adjacent parenchyma. Contrast-enhanced computed tomography (CT) confirmed the diagnosis of HCB based on key imaging features, including homogeneity, isoattenuation relative to the renal cortex, and preservation of normal renal architecture. No signs of necrosis, distortion, or abnormal enhancement were observed. This case highlights the importance of recognizing the characteristic imaging features of HCB to prevent misdiagnosis and avoid unnecessary intervention. In asymptomatic patients, conservative management with imaging follow-up is an appropriate and safe approach.